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Posted: Sat Sep 12, 2009 2:23 pm
by nosebleedXD
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the abs pipe cap doesnt go all the way in so i was wondering

the bb's would fall to the front in front of the vortex block would this matter or

am i suppose to use a cap or what?

cause i see most guns dont have a cap like for example
http://www.spudfiles.com/forums/files/dscf2980_707.jpg

Posted: Sun Sep 13, 2009 11:04 am
by noname
The cap shouldn't matter all that much. However, that vortex block will most likely cause some feed issues.
The barrel isn't flush with the top of the hole. This will basically turn the block into a tiny cloud chamber.
Also, you have a quarter inch or so of material underneath the block. This will make it so that the last few rounds won't load or fire.
<a href="http://www.spudfiles.com/uploader/uploa ... >Here's</a> how I make them. They fire well without shrouds and fire every round in the chamber with no jams.

Posted: Sun Sep 13, 2009 11:24 am
by nosebleedXD
yeah i realized that when i was test firing last night

ima try making a block again

do you have any suggestions of what to use for the shrouds

would cardboard be ok or etc

and for the material underneath the block, do i just shove something underneath it like so

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Posted: Sun Sep 13, 2009 6:28 pm
by nosebleedXD
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does it look ok now?

Posted: Sun Sep 13, 2009 10:40 pm
by noname
You want nothing underneath the vortex hole. Best performance is when the hole is touching the bottom of the chamber.
Any kind of little lip at all will keep the last few BBs from feeding, think about it. It's quite simple to understand. :wink:

Posted: Mon Sep 14, 2009 10:30 am
by nosebleedXD
gotcha =] my block is fine right

Posted: Tue Sep 15, 2009 5:04 pm
by noname
It should work alright, but you might want to slap some shrouds on and cut the bottom 1/4" of the block off. Just a performance thing, it should work as is though.

Posted: Tue Sep 15, 2009 5:08 pm
by nosebleedXD
wait wait cut the bottom of the block off?

wouldn't that make my circle into a half circle?

and the shroud for sure

Posted: Tue Sep 15, 2009 5:21 pm
by Davidvaini
I actually don't like cutting the bottom of the block off, as this hinders the air from creating a vortex which can lower ROF with the same amount of air being pushed into the gun and thus dropping efficiency.

Sometimes with a burst of air it pushes the BB but the BB misses the first time, with a full circle sometimes the BB can twirl around from that first initial blast and chamber itself into the barrel the second time around.

If you chop off the bottom corner, the BB doesn't have the chance to twirl around again on that first blast of air.. instead it has to be bush via the plunger into the air stream again.

So why not use the air that pushed the BB around instead of wasting it?
If you have the full circle, any BB that doesnt get chambered has a second, third, or even a fourth chance of being chambered all within a split second. If you cut off the bottom, any BB that doesn't get chambered drops, gets pushed via the plunger into the air stream and therefore has created a longer time between chambering.

Posted: Tue Sep 15, 2009 6:33 pm
by nosebleedXD
im not really getting whats going on with chopping the thing but yeah i need to make a shroud 0_0

thanks guys

Posted: Tue Sep 15, 2009 10:41 pm
by noname
Davidvaini wrote:I actually don't like cutting the bottom of the block off, as this hinders the air from creating a vortex which can lower ROF with the same amount of air being pushed into the gun and thus dropping efficiency.

Sometimes with a burst of air it pushes the BB but the BB misses the first time, with a full circle sometimes the BB can twirl around from that first initial blast and chamber itself into the barrel the second time around.

If you chop off the bottom corner, the BB doesn't have the chance to twirl around again on that first blast of air.. instead it has to be bush via the plunger into the air stream again.

So why not use the air that pushed the BB around instead of wasting it?
If you have the full circle, any BB that doesnt get chambered has a second, third, or even a fourth chance of being chambered all within a split second. If you cut off the bottom, any BB that doesn't get chambered drops, gets pushed via the plunger into the air stream and therefore has created a longer time between chambering.
The big difference I've found is that BBs can simply pile into the barrel much faster, which ends up wasting less air than a full circle design. In the time it takes for one BB to swirl around one or two or three or four times, another 10 or 15 BBs can be fired, with the same amount of air being put into the system of course.

Posted: Tue Sep 15, 2009 11:34 pm
by Technician1002
Davidvaini wrote:
So why not use the air that pushed the BB around instead of wasting it?
If you have the full circle, any BB that doesnt get chambered has a second, third, or even a fourth chance of being chambered all within a split second. If you cut off the bottom, any BB that doesn't get chambered drops, gets pushed via the plunger into the air stream and therefore has created a longer time between chambering.
I'm not ready to build a BBMG, but I have given it some thought. So here is my 2 cents worth. If the chamber was a section of threaded pipe, they could be ordered in a groove as they spin so they exit in line with the barrel with less impacts from off center projectiles. Even a chamber motor to spin the air and BB will leave more energy for projectile delivery as the projectiles can enter the barrel with higher average velocity.

I thinking any BB that doesn't properly chamber for whatever reason could continue to spin following the thread grove and eject itself off the end and return to the hopper. This could cause the occasional over full chamber from remaining plugged. Excess would auto purge themselves leaving the track clear for the hopper to dribble BBs into the path to pick up speed to enter the barrel at high speed.

Do you think it may improve average projectile speed and rate of fire?

Posted: Tue Sep 15, 2009 11:53 pm
by noname
That's an interesting idea, Technician, although is has been thought of before to some extent.
The chamber motor spinning the air to increase BB velocity seems somewhat feasible. However, it seems too difficult to implement for the marginal (if any) gain in muzzle velocity. Of course, without proper testing, whatever I think could be completely wrong.
Having a vortex in a threaded portion of pipe is a thought that I've seen maybe twice or three times previously, although it's never been actually done as far as I know.
Having the unfired BBs follow a groove back into the hopper doesn't strike me as a hugely fantastic idea though. I'd prefer covering a whole side of the vortex block in that case, so that there just wouldn't be any unfired BBs. But obviously that's just making a sidestrafer right side up.

I don't really understand what you mean by "over full chamber" and "remaining plugged."

Posted: Wed Sep 16, 2009 1:56 am
by Technician1002
noname wrote:
I don't really understand what you mean by "over full chamber" and "remaining plugged."
Try merging onto a freeway where there was an accident and all the cars are sideways in a pile. The raceway for the bb's needs to be kept clear for those on the ramp at high speed. If not the pileup continues and the traffic never gets moving at high speed with high rate of car merges.

The idea is to prevent saturation of the area near the barrel with slow moving obstacles. They should have an exit ramp to get out of the way.

Posted: Wed Sep 16, 2009 8:23 am
by noname
A sidestrafer has an exit ramp, it's the barrel.